Parallel Linear Algebra Features
This lists all missing features and todos for the implementation of parallel linear algebra.

General interface 
Parallel examples/ tests 
MTL 
ISTL 
Overlapping Schwarz 
Nonoverlapping Schwarz 
Case overlapSize + ghostSize == 0


Bases with more than one DoF per entity 
e.g. Lagrange order 3+, edge/face twists 
LagrangeDG


More parallel preconditioners


EIGEN 
PETSc